Management of Ureteropelvic Junction Obstruction (UPJO) Caused by Schistosomiasis
Treat all patients with UPJO secondary to schistosomiasis with praziquantel 40 mg/kg as a single oral dose, followed by surgical intervention (ureteral resection with reconstruction or pyeloplasty) if significant obstruction persists after antiparasitic therapy, as medical treatment alone cannot reverse established fibrotic strictures. 1, 2, 3
Initial Diagnostic Workup
Confirm Active Schistosomal Infection
- Obtain microscopy of terminal urine samples to detect Schistosoma haematobium eggs, as this confirms active infection requiring treatment 4
- Test for endemic coinfections including Salmonella, HBV, HCV, and HIV, as these may alter disease aggressiveness and treatment approach 1, 5
- Perform renal ultrasound to assess degree of hydronephrosis and identify ureteral dilation or stricture 1
Assess Severity of Obstruction
- Obtain Tc-99m MAG3 renal scan to evaluate split renal function and drainage, as this determines urgency of intervention 1
- Consider CT or MRI for detailed anatomical assessment of the ureteropelvic junction and surrounding structures, particularly to exclude malignancy which can mimic schistosomal obstruction 6
- Evaluate for bladder cancer and urinary obstruction in patients with elevated creatinine and/or hematuria, as these are common complications of S. haematobium 1, 5
Medical Management
Antiparasitic Treatment
- Administer praziquantel 40 mg/kg orally as a single dose immediately upon diagnosis 1, 2, 5
- Repeat praziquantel 40 mg/kg at 6-8 weeks after initial treatment, as immature schistosomules are relatively resistant to initial therapy 2, 4
- Do not use immunosuppressive agents in schistosomal nephropathy or urinary tract disease, as these provide no benefit and may worsen outcomes 1, 5
Symptomatic Management
- Consider short course of oral prednisolone 20 mg daily for 5 days if acute inflammatory symptoms are severe, though this does not affect cure rates 2, 4
Surgical Intervention
Indications for Surgery
Proceed with surgical intervention when any of the following criteria are met after completing antiparasitic therapy:
- T1/2 >20 minutes on diuretic renal scan indicating persistent obstruction 1
- Differential renal function <40% on affected side 1
- Deteriorating function with >5% decrease on consecutive renal scans 1
- Progressive hydronephrosis on serial ultrasound despite medical treatment 3, 7
Surgical Options
- Perform ureteral resection with Boari flap and psoas hitch reconstruction for lower ureteral strictures with severe fibrosis 3
- Consider open, laparoscopic, or robotic pyeloplasty for ureteropelvic junction strictures 8
- Place percutaneous nephrostomy for temporary drainage in patients with severe uremia or acute obstruction while planning definitive surgery 7
- Use ureteral stenting for attempted recannalization in select cases, though definitive reconstruction is often ultimately required 7
Critical Timing Considerations
The key pitfall in schistosomal UPJO is delayed surgical intervention. Medical treatment with praziquantel eradicates the parasite but cannot reverse established fibrotic strictures 3, 6. Waiting too long after antiparasitic therapy risks progressive renal damage and irreversible loss of function 3, 7.
- Complete both doses of praziquantel (initial and 6-8 week repeat) before surgical planning 2, 4
- Reassess with renal scan 2-3 months after completing antiparasitic therapy to determine if obstruction persists 1
- Do not delay surgery beyond 3-4 months post-treatment if objective evidence of obstruction remains, as progressive renal deterioration is likely 3, 7
Monitoring and Follow-up
- Perform serial ultrasound every 3-6 months after surgery to monitor for recurrent obstruction 1
- Repeat renal scan if differential function was impaired pre-operatively to document improvement or stability 1
- Do not use serology to assess treatment success, as antibodies persist for years after successful parasite eradication 2, 4, 5
- Monitor for bladder complications including stones, strictures, and malignancy with periodic cystoscopy in patients with history of urinary schistosomiasis 7, 6
Special Populations
Patients with Renal Insufficiency
- Initiate maintenance hemodialysis if severe uremia is present while planning definitive surgical management 7
- Prioritize early surgical decompression to preserve remaining renal function 3, 7